Fix received/1 and sent/1 function spec

src/emqttd_cli.erl

@@ -249,8 +249,6 @@ subscriptions(["add", ClientId, Topic, QoS]) ->
            case emqttd:subscribe(bin(Topic), bin(ClientId), [{qos, IntQos}]) of
                ok ->
                    ?PRINT_MSG("ok~n");
-               {error, already_existed} ->
-                   ?PRINT_MSG("Error: already existed~n");
                {error, Reason} ->
                    ?PRINT("Error: ~p~n", [Reason])
            end

src/emqttd_metrics.erl

@@ -102,7 +102,7 @@ start_link() ->
     gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
 
 %% @doc Count packets received.
--spec(received(mqtt_packet()) -> ok).
+-spec(received(mqtt_packet()) -> ignore | non_neg_integer()).
 received(Packet) ->
     inc('packets/received'),
     received1(Packet).
@@ -140,7 +140,7 @@ qos_received(?QOS_2) ->
     inc('messages/qos2/received').
 
 %% @doc Count packets received. Will not count $SYS PUBLISH.
--spec(sent(mqtt_packet()) -> ok).
+-spec(sent(mqtt_packet()) -> ignore | non_neg_integer()).
 sent(?PUBLISH_PACKET(_Qos, <<"$SYS/", _/binary>>, _, _)) ->
     ignore;
 sent(Packet) ->
@@ -169,7 +169,7 @@ sent2(?UNSUBACK) ->
 sent2(?PINGRESP) ->
     inc('packets/pingresp');
 sent2(_Type) ->
-    ingore.
+    ignore.
 qos_sent(?QOS_0) ->
     inc('messages/qos0/sent');
 qos_sent(?QOS_1) ->